.yijian {
    width: 90%;
    height: 450px;
    background: #fff;
    margin: 20px;
    border-radius: 10px;
}

.yijian h3 {
    padding: 20px;
    font-weight: normal;
}

.card {
    height: 30px;
    display: flex;
    border-bottom: 1px solid #f6f6f6;
}
.btn{
    position: fixed;
    bottom: 0;
    width: 100%;
    height: 90px;
    background: #fff;
}